It’s hard to convince teens to do anything they don’t want to, but new research shows that when it comes to losing weight, a program that leaves parents out of the picture may help.

The study, published in the journal Pediatrics, involved 208 overweight or obese teen girls aged 12 to 17, who were living in Oregon and Washington in 2005-09. The girls were assigned either to receive usual weight-loss advice or to participate in a moderately intensive behavioral program that stressed healthy eating and exercise habits. The twist? The teens’ parents were given separate sessions about how to support their daughters in their weight-loss efforts. In contrast, most previous youth weight loss studies have offered treatment to families all together.

After six months, all of the girls were evaluated for weight and height to calculate their body mass index, or BMI; six months later, they were measured again. By the end of the yearlong interval, the teens in the behavioral program showed only slightly lower BMIs than the control group on average, but they reported having significantly better body image and had adopted healthier eating habits. Specifically, the teens in the behavior-modification program ate more meals together with their families, which previous studies have shown promotes healthier eating, ate less fast-food and consumed more fruits and vegetables.

“We purposefully set up the study not expecting people to have very dramatic and quick weight losses, but emphasizing different tools in terms of dietary changes and physical activity that we thought would be easy to include in every life, and which could be sustained over time,” says Lynn DeBar, senior investigator at Kaiser Permanente Center for Health Research and the study’s lead author. “We suspected these would have more staying power than a more calorically focused weight management regimen.”

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Indeed, while the girls on the program didn’t lose a remarkable amount of weight, especially compared with other weight-loss regimens, DeBar says the results are still significant because they are the first to show that a teen-centered approach to weight loss can be effective. What’s more, because it did not focus on calorie-counting, the adolescent girls may have been more likely to embrace the behavior changes.

The behavioral program involved 90-min. group sessions that occurred 16 times over the study’s five-month period, during which teens met with specially trained counselors to discuss how to change their eating patterns and become more physically active by using exergames and incorporating 15 minutes of yoga daily. The girls also spoke with counselors about body image and eating disorders.

To change their eating habits, the counselors emphasized decreasing portion sizes and advised the teens on eating fewer high-calorie foods and more lower-calorie options such as fruits and vegetables. They also talked to the adolescents about substituting water for sugared sodas, and the importance of eating regular meals, especially breakfast.

To encourage the teens to exercise more, the program provided yoga equipment as well as exergames such as Dance Dance Revolution, which the girls could use on their own or with friends and which researchers figured they would enjoy more than regimented sessions at a gym. The researchers advised the teens to incorporate 30 to 60 minutes of physical activity a day, five days a week.

At the start of the study and again six months later, the teens also visited their pediatricians to discuss concerns about weight. The pediatricians were trained to be more attentive to weight issues and to work collaboratively with the girls to find the best way to adopt a healthier lifestyle.

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The control group was given a packet of information on weight-loss strategies, books and online materials, as well as contacts to local resources for weight management. They also met with primary care physicians at the beginning of the study to discuss healthy lifestyle changes, but these doctors were not provided with the specialized training to address teens’ weight issues.

Overall, the behavioral program seemed to be effective in giving teens the right tools with which to maintain healthy weight over the long term. After six months, the girls in the program had reduced their sedentary TV and computer time by 5 hours and consumed 240 fewer calories per day on average, compared with the control group.

Part of the program’s success may be due to the fact that unlike specialized or clinic-based weight management programs, which are more structured and conducted over limited periods of time, this program involved the teens’ pediatricians, with whom the girls have ongoing relationships. “The idea was to see if we could have a weight loss program that involved primary care providers, since formal weight management programs are time limited, meaning people do well during the program but then lose their improvements over time,” says DeBar. “We thought that since the girls have an ongoing relationship with their pediatrician, that would allow what they are doing to be reinforced and sustained over a longer period of time.”

It did, and giving the adolescent girls more autonomy over their weight loss options, without directly involving Mom and Dad, also helped. Still, there is a limit to how much control teens should be allowed to have over their diets, since studies also show that when parents are more involved in helping children decide what to eat — particularly by adopting the same diet and exercise changes that their children do — youngsters are more likely to learn and maintain healthier eating habits.

Alice Park is a writer at TIME. Find her on Twitter at @aliceparkny. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.

Read more: http://healthland.time.com/2012/02/13/do-teen-weight-loss-programs-work-better-without-mom-or-dad/#ixzz1mRJT9YRJ